[amsat-bb] Re: ARRL dual moxon turnstyle project questions

[Reicher, James]

Scott, 

1. I would recommend using standard connectors and teeing them rather
than soldering to a lug.  You'll find that if you want to move the array
for portable work, it will be easier to set up and take down.

2.  Although I'm no expert, I wouldn't think you'd even need the same
length feedline, although it couldn't hurt.

3.  LB gives the dimensions in inches, but try converting them to
millimeters.  Just multiply by 25.4 millimeters to the inch.  I'd round
to the nearest 1/2 mm and cut as close as possible.  Then, that ".49
inches" dimension becomes 12.5 mm.  

4.  You could always use duct tape... they use it on the shuttle and
ISS!


BTW, the 70cm version calls for #12 AWG wire, not #14.  


73 de N8AU, Jim in Raymore, MO
 
Light travels faster than sound...  This is why some people appear
bright until you hear them speak.


Date: Tue, 31 Jul 2007 07:08:16 -0700 (PDT)
From: Scott Wilson <s.wilson at yahoo.com>
Subject: [amsat-bb]  ARRL dual moxon turnstyle project questions
To: amsat-bb at amsat.org
Message-ID: <862339.97515.qm at web31810.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1

I'm working on building the ARRL dual moxon antennas, but the article
isn't very detailed where I'd like it to be and a little over detailed
in
some places I wish it weren't.

If you want to look, this is the URL
(http://www.arrl.org/members-only/tis/info/pdf/0108038.pdf)

1. What are acceptable ways to terminate the paralled 75 ohm matching
sections? I'm thinking now I'll just terminate them to a couple of ring
terminals attached to the mast rather than terminating each one with a
bnc
and teeing them.

2. How do I feed the 70cm and 2m with the same feedline? should I just
tee
a 50 ohm line to two equal length 50 ohm sections?

3. This is more of a comment... I'm wagering the uhf version doesn't
work
at all... measurements are given to the hundreth of an inch - and then
you
solder a big ring lug to the end of it!

4. Are there any other good techniques for setting the distance between
the reflector and driver besides heat shrink?

The 70cm antenna is using #14 galvanized wire, and I can't think of
anything small enough to hold them in place well. I found that the 3/16
rod for the 2m moxon will work great with 1/4" nylon tubing.

Thanks for any feedback - I'll probably have more questions.. I'm
sitting
here with a half-made 70cm turnstyle, and am about to start on the 2m
version.

Whew - I'm beginning to think that a $1000 investment in rotators and
antennae isn't such a bad idea after all!

Scott Wilson
NW2S